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Fluorescence labeling of polysaccharides
Mrázová, Viktória ; Venerová, Tereza (referee) ; Mravec, Filip (advisor)
This bachelor’s dissertation deals with the study of fluorescence-marked polysaccharides. The aim of this project was to develop and define fluorescence-marked dextran, chitosan, hyaluronan, and their derivatives. These substances were developed by binding a fluorescent marker and a polysaccharide through covalent bonding. First, we developed samples of a polysaccharide that were marked with a fluorophore. For utilising this method, we considered suitable the following combinations: FITC+ dextran, FITC+ chitosan, and fluorescein amine+ hyaluronan. Following this, we defined these samples using a fluorescence spectrometer, which allowed us to measure the fluorescence properties of the derivatives of the selected marked polysaccharides. Using this measuring method, we found that a covalent bond does occur between the fluorescent marker and the polysaccharides. Finally, we compared the economic cost of developing these substances, as opposed to buying them commercially.
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Hydration of biocolloids - calorimetric study
Šméralová, Ester ; Pekař, Miloslav (referee) ; Klučáková, Martina (advisor)
Presented master's thesis focuses on the study of hydration of selected biocolloid substances, specifically humic substances (humic acids and fulvic acids), hyaluronic acid with three different molecular weight, chitosan and dextran. Interaction of biocolloids with water was studied by different methods. The effect of solubility, structure, functional groups in molecule on sorption and hydration ability of these biocolloids was investigated. In the case of hyaluronan the influence of molecular weight was also study. Differential scanning calorimetry DSC and perfusion calorimetry give results of heat of hydration, enthalpies and temperature of crystallization and melting. Thermogravimetric analysis TGA was used to determine the original moisture content of the samples.
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Hydration of biopolymers
Šméralová, Ester ; Smilková, Marcela (referee) ; Klučáková, Martina (advisor)
Presented bachelor's thesis focuses on the study of hydration of selected biopolymers – humic acids, chitosan, hyaluronic acid (low molecular weight and high molecular weight) and dextran. Thermogravimetric analysis TGA is used t determine the original moisture content of the samples. Two calorimetric methods were used for subsequent observations of changes in their chemical and mechanical properties in the presence of water – differential scanning calorimetry DSC and perfusion calorimetry.
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Study of hydration of biocolloids
Hývnarová, Lucie ; Sedláček, Petr (referee) ; Klučáková, Martina (advisor)
The subject of this master’s thesis was to examine the hydration properties of selected biocolloids. Specifically, humic substances (fulvic and humic acids), hyaluronic acids in three molecular weights, dextran and chitosan were investigated. Hydration properties of selected biocolloid substances were studied by various methods. The influence of water content during the dissolution of substances and the different time for which water acted on biocolloids were studied. Differential scanning calorimetry DSC measurements resulted in enthalpies and crystallization and melting points. Heat fluxes resulted in the use of perfusion calorimetry. TGA thermogravimetric analysis was used to determine the moisture content of the bioolloids used, after measuring the perfusion calorimeter.
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Fluorescence labeling of polysaccharides
Mrázová, Viktória ; Venerová, Tereza (referee) ; Mravec, Filip (advisor)
This bachelor’s dissertation deals with the study of fluorescence-marked polysaccharides. The aim of this project was to develop and define fluorescence-marked dextran, chitosan, hyaluronan, and their derivatives. These substances were developed by binding a fluorescent marker and a polysaccharide through covalent bonding. First, we developed samples of a polysaccharide that were marked with a fluorophore. For utilising this method, we considered suitable the following combinations: FITC+ dextran, FITC+ chitosan, and fluorescein amine+ hyaluronan. Following this, we defined these samples using a fluorescence spectrometer, which allowed us to measure the fluorescence properties of the derivatives of the selected marked polysaccharides. Using this measuring method, we found that a covalent bond does occur between the fluorescent marker and the polysaccharides. Finally, we compared the economic cost of developing these substances, as opposed to buying them commercially.
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Diffusion of dyes in biopolymeric hydrogels
Vyroubal, David ; Mravec, Filip (referee) ; Klučáková, Martina (advisor)
This thesis is focused on diffusion of dyes in biopolymer-based hydrogels. These hydrogels are based on interaction between biopolymer-like electrolytes with oppositely charged surfactants. When polyelectrolytes interact with oppositely charged surfactants, micelle-like nano-containers can be formed. These nano-containers are able of binding hydrophobic compounds. In this study, combination of modified dextran (diethylaminoethyl dextran) with positive charge and oppositely charged sodium dodecylsulphate as surfactant was used for preparation of hydrogels. Next type of hydrogel was based on hyaluronan and positive charged surfactant Septonex (carbethoxypendecinium bromide). As a diffusion probes in hydrogels dyes Nile red and ATTO 488 were used. The diffusion of these dyes from aqeous solutions of NaCl or surfactants into hydrogels was monitored in time. Transport of dyes into structure of hydrogels was characterized by diffusion coefficients and structural parameters of hydrogels.
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Hydration of biocolloids - calorimetric study
Šméralová, Ester ; Pekař, Miloslav (referee) ; Klučáková, Martina (advisor)
Presented master's thesis focuses on the study of hydration of selected biocolloid substances, specifically humic substances (humic acids and fulvic acids), hyaluronic acid with three different molecular weight, chitosan and dextran. Interaction of biocolloids with water was studied by different methods. The effect of solubility, structure, functional groups in molecule on sorption and hydration ability of these biocolloids was investigated. In the case of hyaluronan the influence of molecular weight was also study. Differential scanning calorimetry DSC and perfusion calorimetry give results of heat of hydration, enthalpies and temperature of crystallization and melting. Thermogravimetric analysis TGA was used to determine the original moisture content of the samples.
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Time-temperature superposition principle used for study of rheological properties of polymer materials
Kadlec, Martin ; Jarábková, Sabína (referee) ; Smilek, Jiří (advisor)
This bachelor thesis provides a study of the “time-temperature superposition” principle and its applicability to hydrogels. According to current research, honey was chosen due to its simple viscoelastic properties (Newtonian liquid) as a suitable material for optimalization procedure. The knowledge obtained during optimization was further applied to real hydrogel materials, namely the agarose gel was selected as an example of thermoreversible hydrogel, as well as the hyaluronan and dextran gels as examples of hydrogels formed by the interaction of the polyelectrolyte with the opposite charged surfactant. By using the “time-temperature superposition” principle, a considerable increase in the range of the observed oscillation frequencies was achieved for all chosen samples, which led to gain of information about storage and loss or complex modulus, which could not be achieved by classical oscillatory test. Although master curves were generated for all the samples examined, curves for storage and loss modulus could be created separately only for hydrogels formed by the interaction of the polyelectrolyte with the opposite charged surfactant. For this reason, this group of hydrogels appears to be more suitable materials for the application of the “time-temperature superposition” principle.
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Fluorescence probes to study the properties of hydrogel systems
Máčala, Jakub ; Venerová, Tereza (referee) ; Mravec, Filip (advisor)
This bachelors thesis is focused on possibility of selected fluorescent probes for study of properties of hydrogel systems. Chosen probes are Prodan for polarity study, HPTS for measurement of pH of the probe environment and platinum complex [2,6-Bis(2-pyridyl)fenyl-C,N,N]chloroplatinum(II) for its unique fluorescence properties and potential of energy transfer studies in hydrogel systems. Spectral properties of fluorophores were defined in selected set of solvents with different polarity with steady state fluorescence spectroscopy method. Properties of HPTS probe were also tested in buffers with different pH. Subsequently, hydrogels based on hyaluronan-septonex and dextran-SDS with incorporated fluorescence probes were prepared. Steady state fluorescence measurement of fluorophores from hydrogel were made using fluorimeter optical fibres. It was found, that probes Prodan and HPTS are suitable for study of polarity and pH of hydrogels and probably they will be able to be used for study of hydrogel with other techniques, like fluorescence microscopy, however platinum complex is, due to the low fluorescence intensity and possible quenching by polar water environment, probably not suitable for other measurements.
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